TinkerPop Gremlin, how get child elements filtered and grouped

Question

I'm new to using Gremlin and I need help to set the best query to select unique and filtered results.

Starting from a team I would get player (note: each player can play for more than one team) of each team connected by is_friends_with

The result (I would like to get)

[
 {
   "Player": "Icardi",
   "Teams": ["Valladolid"]
 },
 {
   "Player": "Kroll",
   "Teams": ["Valladolid"]
 },

  {
   "Player": "Baggio",
   "Teams": ["Eagles"]
 },

 {
   "Player": "Papin",
   "Teams": ["Valladolid","Eagls"]
 },
]

The graph

The schema:

 g.addV('team').as('1').
 property(single, 'name', 'Eagles').
 addV('player').as('2').
 property(single, 'name', 'Zico').addV('team').
 as('3').
 property(single, 'name', 'team A').
 addV('team').as('4').
 property(single, 'name', 'Horses').
 addV('player').as('5').
 property(single, 'name', 'Papin').
 addV('player').as('6').
 property(single, 'name', 'Ronaldo').
 addV('player').as('7').
 property(single, 'name', 'Visco').
 addV('player').as('8').
 property(single, 'name', 'Baggio').
 addV('tournament').as('9').
 addV('team').as('10').
 property(single, 'name', 'Valladolid').
 addV('player').as('11').
 property(single, 'name', 'Kroll').
 addV('player').as('12').
 property(single, 'name', 'Icardi').
 addE('owned').from('1').to('5').addE('owned').
 from('1').to('6').addE('owned').from('1').
 to('8').addE('owned').from('3').to('6').
 addE('owned').from('3').to('7').
 addE('created').from('3').to('9').
 addE('is_friends_with').from('3').to('10').
 addE('is_friends_with').from('3').to('1').
 addE('owned').from('4').to('8').addE('owned').
 from('4').to('2').addE('owned').from('4').
 to('5').addE('owned').from('4').to('7').
 addE('invited').from('9').to('1').
 addE('invited').from('9').to('4').
 addE('owned').from('10').to('11').
 addE('owned').from('10').to('12').
 addE('owned').from('10').to('5')

score 1 · Accepted Answer · answered Feb 19 '22 at 17:17

Here is one way to do it using group

gremlin>  g.V().
......1>    has('name','team A').
......2>    out('is_friends_with').as('a').
......3>    out('owned').
......4>    group().
......5>      by('name').
......6>      by(select('a').values('name').fold()).
......7>    unfold()

==>Papin=[Valladolid, Eagles]
==>Icardi=[Valladolid]
==>Baggio=[Eagles]
==>Ronaldo=[Eagles]
==>Kroll=[Valladolid]

To get the exact format that matches your JSON, we can just add aproject step to the query.

gremlin>  g.V().
......1>    has('name','team A').
......2>    out('is_friends_with').as('a').
......3>    out('owned').
......4>    group().
......5>      by('name').
......6>      by(select('a').values('name').fold()).
......7>    unfold().
......8>    project('player','teams').
......9>      by(keys).
.....10>      by(values)

==>[player:Papin,teams:[Valladolid,Eagles]]
==>[player:Icardi,teams:[Valladolid]]
==>[player:Baggio,teams:[Eagles]]
==>[player:Ronaldo,teams:[Eagles]]
==>[player:Kroll,teams:[Valladolid]]

Thanks! It is similar to my own solution, but it works! Very interesting and... light! I really appreciated your help! — Uncoke, Feb 20 '22 at 05:35

score 1 · Answer 2 · answered Feb 20 '22 at 03:05

gremlin> g.V().has("name", "team A").sideEffect(__.out("owned").hasLabel("player").aggregate("my_player").limit(1)).both("is_friends_with").hasLabel("team").as("team2").out("owned").hasLabel("player").as("friends_player").where(without("my_player")).as("friends_player2").select("team2", "friends_player2").group().by(select("friends_player2")).by(select("team2").fold()).unfold().project("Player", "Teams").by(select(keys).values("name")).by(select(values).unfold().values("name").fold())

==>[Player:Baggio,Teams:[Eagles]]
==>[Player:Kroll,Teams:[Valladolid]]
==>[Player:Icardi,Teams:[Valladolid]]
==>[Player:Papin,Teams:[Valladolid,Eagles]]

As it’s currently written, your answer is unclear. Please [edit] to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers [in the help center](/help/how-to-answer). — Community, Feb 20 '22 at 16:12

TinkerPop Gremlin, how get child elements filtered and grouped

2 Answers2